Joint assembly of a car windshield wiper arm

Abstract

An upper cover body has left and right grooves between a solid core and left and right sides; a round groove near a front side; a rear facing receptacle across a rear of the solid core; the left and right sides including left and right ribs extending to the rear end encompassing a hollow socket; an elastic embed hook on the rear end corresponding with the receptacle and having a forward facing nose. A chassis has a bottom plate, left and right plates extending upward from respective sides of the bottom plate, and a rear plate; a fixing hole in the bottom plate; an upright curbing plate at the rear end of the bottom plate; a front horizontal fixing pivot between the left and right plates; an upright hollow plug encompassed by the left, right, and rear plates; an insetting hole centered in the rear plate.

1. A joint of a car windshield wiper arm, comprising:
 an upper cover body having a front side, a top side, a bottom side, a left side, a right side, a rear end, and a solid core between said left side and said right side; wherein a left groove cut is formed upward from said bottom side between said left side and said solid core, and a right groove cut is formed upward from said bottom side between said right side and said solid core; a round groove cut with V-shaped cross-section is concaved near said front side; a trapezohedron receptacle is formed horizontally across a rear of said solid core having a rear facing opening; said left side and right side respectively including a parallel and symmetrical left rib and right rib, said left rib and said right rib extending from below said trapezohedron receptacle rearward to said rear end to encompass a hollow socket; an elastic upright embed hook is built and centered on a top surface of said rear end in correspondence with said trapezohedron receptacle; a horizontal insetting nose is formed in a middle section of said elastic upright embed hook with direction facing towards said hollow socket; and 
 a chassis having a bottom plate, a left plate, a right plate and a rear plate; wherein, a fixing hole is perforated at the center of said bottom plate; a pair of parallel and symmetrical inset clips are concaved between said fixing hole and a front edge of said bottom plate; said left plate and right plate are extended upward from respective left and right sides of said bottom plate, the left plate and right plate being parallel and symmetrical; an upright curbing plate is formed by bending the rear end of said bottom plate upwards; a horizontal fixing pivot is bridged between said left plate and said right plate near the front end; an upright hollow plug is encompassed by extending a middle section of said left plate and said right plate backwards to said rear plate; an insetting hole is perforated at the center of said rear plate.